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He has a healthy self-confidence, I can tell from his posturing.
— Rabbi Jacob “Jake” Schram · Keeping the Faith
Behind the line May contain spoilers.
Our reading
An editorial interpretation.
A dry observation: the speaker reads another man's body language and concludes he's confident, and healthily so. The joke sits in "posturing," which usually sounds like showing off, so the compliment comes with a gentle, sly poke at how he carries himself.
Context reviewed